OPTIMAL DETECTION OF APOPTOSIS BY FLOW-CYTOMETRY DEPENDS ON CELL MORPHOLOGY

Flow cytometry has recently become a choice technique for the quantita tive analysis of apoptosis. Monoparametric DNA analysis usually allows identification of apoptotic cells as a ''subdiploid'' peak. Progressi on through apoptosis leads to chromatin condensation, nuclear fragment ation and eventually to cell disruption. Thus, a major problem for the flow cytometric analysis of apoptotic populations is discrimination b etween debris and apoptotic cells. Here we demonstrate that the best, parameter on which to make such a distinction is the DNA content, no m atter what type of cell is studied. In contrast, discrimination betwee n apoptotic, non-apoptotic cells, and debris is possible on the basis of scattering signals only in few selected cases, depending on the mor phology of the intact cells. (C) 1993 Wiley-Liss, Inc.